Merge pull request #79 from Mapotempo/add_dynamic_attribute

Add dynamic attribute

lib/couchbase-orm.rb

@@ -15,6 +15,7 @@ module CouchbaseOrm
     autoload :Document,        'couchbase-orm/base'
     autoload :NestedDocument,   'couchbase-orm/base'
     autoload :HasMany,     'couchbase-orm/utilities/has_many'
+    autoload :AttributesDynamic,  'couchbase-orm/attributes/dynamic'
 
     def self.logger
         @@logger ||= defined?(Rails) ? Rails.logger : Logger.new(STDOUT).tap { |l| l.level = Logger::INFO unless ENV["COUCHBASE_ORM_DEBUG"] }

lib/couchbase-orm/attributes/dynamic.rb

@@ -0,0 +1,99 @@
+# frozen_string_literal: true, encoding: ASCII-8BIT
+
+module CouchbaseOrm
+    module AttributesDynamic
+        extend ActiveSupport::Concern
+
+        # Override respond_to? so it responds properly for dynamic attributes.
+        #
+        # @example Does this object respond to the method?
+        #   person.respond_to?(:title)
+        #
+        # @param [ Array ] name The name of the method.
+        # @param [ true | false ] include_private
+        #
+        # @return [ true | false ] True if it does, false if not.
+        def respond_to?(name, include_private = false)
+            super || attributes&.key?(name.to_s.reader)
+        end
+
+        private
+
+        # Override private _assign_attribute to accept dynamic attribute
+        #
+        # @param [ String ] name of attribute
+        # @param [ Object ] value of attribute
+        #
+        # @return [ Object ] value of attribute
+        def _assign_attribute(name, value)
+            responds = name.reader == 'id' || respond_to?(name.writer)
+            if responds
+                public_send(name.writer, value)
+            else
+                type = value.class.to_s.underscore.to_sym
+                type = :hash if type == :"active_support/hash_with_indifferent_access"
+                type = ActiveModel::Type.lookup(type)
+                @attributes[name] = ActiveModel::Attribute.from_database(name, value, type)
+            end
+        end
+
+        # Define a reader method  for a dynamic attribute.
+        #
+        # @example Define a reader method.
+        #   model.define_dynamic_reader(:field)
+        #
+        # @param [ String ] name The name of the field.
+        def define_dynamic_reader(name)
+            return unless name.valid_method_name?
+
+            instance_eval do
+                define_singleton_method(name) do
+                    @attributes[getter].value
+                end
+            end
+        end
+
+        # Define a writer method for a dynamic attribute.
+        #
+        # @example Define a writer method.
+        #   model.define_dynamic_writer(:field)
+        #
+        # @param [ String ] name The name of the field.
+        def define_dynamic_writer(name)
+            return unless name.valid_method_name?
+
+            instance_eval do
+                define_singleton_method("#{name}=") do |value|
+                    @attributes.write_from_user(name, value)
+                    value
+                end
+            end
+        end
+
+        # Used for allowing accessor methods for dynamic attributes.
+        #
+        # @api private
+        #
+        # @example Call through method_missing.
+        #   document.method_missing(:test)
+        #
+        # @param [ String | Symbol ] name The name of the method.
+        # @param [ Object... ] *args The arguments to the method.
+        #
+        # @return [ Object ] The result of the method call.
+        def method_missing(name, *args)
+            attr = name.to_s
+            return super unless attr.reader != 'id' && attributes.key?(attr.reader)
+
+            getter = attr.reader
+            if attr.writer?
+                define_dynamic_writer(getter)
+                @attributes.write_from_user(getter, args.first)
+                args.first
+            else
+                define_dynamic_reader(getter)
+                @attributes[getter].value
+            end
+        end
+    end
+end

lib/couchbase-orm/base.rb

@@ -10,6 +10,7 @@
 end
 require 'active_support/hash_with_indifferent_access'
 require 'couchbase'
+require 'couchbase-orm/extensions/string'
 require 'couchbase-orm/error'
 require 'couchbase-orm/views'
 require 'couchbase-orm/n1ql'
@@ -86,7 +87,17 @@ def attribute_for_inspect(attr_name)
             value.inspect
         end
 
-        if ActiveModel::VERSION::MAJOR < 6
+        if ActiveModel::VERSION::MAJOR <= 6
+            def format_for_inspect(value)
+                if value.is_a?(String) && value.length > 50
+                    "#{value[0, 50]}...".inspect
+                elsif value.is_a?(Date) || value.is_a?(Time)
+                    %("#{value.to_s(:db)}")
+                else
+                    value.inspect
+                end
+            end
+
             def attribute_names
                 self.class.attribute_names
             end
@@ -104,6 +115,14 @@ def _write_attribute(attr_name, value)
                 @attributes.write_from_user(attr_name.to_s, value)
                 value
             end
+
+            def read_attribute(attr_name, &block)
+                name = attr_name.to_s
+                name = self.class.attribute_aliases[name] || name
+
+                name = @primary_key if name == "id" && @primary_key
+                @attributes.fetch_value(name, &block)
+            end
         end
     end
 

lib/couchbase-orm/extensions/string.rb

@@ -0,0 +1,27 @@
+module CouchbaseOrm
+    module Extensions
+        module String
+            def reader
+                delete("=").sub(/\_before\_type\_cast\z/, '')
+            end
+
+            def writer
+                sub(/\_before\_type\_cast\z/, '') + "="
+            end
+
+            def writer?
+                include?("=")
+            end
+
+            def before_type_cast?
+                ends_with?("_before_type_cast")
+            end
+
+            def valid_method_name?
+                /[@$"-]/ !~ self
+            end
+        end
+    end
+end
+
+::String.__send__(:include, CouchbaseOrm::Extensions::String)

lib/couchbase-orm/types.rb

@@ -5,7 +5,7 @@
 require "couchbase-orm/types/nested"
 require "couchbase-orm/types/encrypted"
 
-if ActiveModel::VERSION::MAJOR < 6
+if ActiveModel::VERSION::MAJOR <= 6
   # In Rails 5, the type system cannot allow overriding the default types
   ActiveModel::Type.registry.instance_variable_get(:@registrations).delete_if do |k|
     k.matches?(:date) || k.matches?(:datetime) || k.matches?(:timestamp)

spec/attribute_dynamic_spec.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true, encoding: ASCII-8BIT
+
+require File.expand_path("../support", __FILE__)
+
+class AttributeDynamicTest < CouchbaseOrm::Base
+     include CouchbaseOrm::AttributesDynamic
+
+     attribute :name, :string
+     attribute :job, :string
+end
+
+describe CouchbaseOrm::AttributesDynamic do
+     context 'from initialize' do
+       it 'should accept unknown attribute from initialize' do
+         dynamic = AttributeDynamicTest.new(name: 'joe', new_attribute: 1)
+         expect(dynamic.new_attribute).to eq(1)
+       end
+     end
+
+     context 'from Couchbase' do
+       it 'should accept unknown attribute from Couchbase' do
+        dynamic = AttributeDynamicTest.create!(name: 'joe', new_attribute: 2)
+        expect(AttributeDynamicTest.find_by_id(dynamic.id)).to have_attributes(new_attribute: 2)
+        dynamic.destroy
+       end
+     end
+end